http_connection_pool_timeout option

Excess connections are deleted at an increasing rate based on this value if the pool size exceeds http_connection_pool_basesize.

Changing this option takes effect within 5 seconds during the next purge cycle. Any unused database connections having exceeded
http_connection_pool_timeout within the http_connection_pool_basesize threshold are deleted. When the size of a connection
pool exceeds the http_connection_pool_basesize threshold, connections are deleted at a more aggressive rate.

Unused excess connections are removed within half the time-out interval, half of the remainder are purged if unused within
a quarter time-out interval, and so on. The following database properties have been added to determine the operating efficiency
of the connection pools within a database: